论文标题
薄环燃烧室中声场的分析溶液，横截面面积和平均温度的线性梯度
Analytical solutions for the acoustic field in thin annular combustion chambers with linear gradients of cross-sectional area and mean temperature
论文作者
论文摘要
环形燃烧器中热声不稳定性的预测是必不可少的但困难的。流量和热参数的轴向变化增加了数值模拟的成本，并限制了分析溶液的应用。这项工作旨在找到具有轴向不均匀横截面和平均温度的线性梯度的环形管中的声场的近似分析解决方案。这些解决方案可以应用于低阶声学网络模型，并增强分析方法解决实际环形室中热声不稳定性问题的能力。修改的WKB方法用于求解声场的波方程，并得出了具有广泛应用的分析解决方案。方程式的推导需要假设，例如低马赫数，高频和较小的不均匀性。只要在整个室内满足假设，就可以通过分段法解决具有横截面面积和平均温度的任意分布的情况。
Predictions of thermoacoustic instabilities in annular combustors are essential but difficult. Axial variations of flow and thermal parameters increase the cost of numerical simulations and restrict the application of analytical solutions. This work aims to find approximate analytical solutions for the acoustic field in annular ducts with linear gradients of axially non-uniform cross-sectional area and mean temperature. These solutions can be applied in low-order acoustic network models and enhance the ability of analytical methods to solve thermoacoustic instability problems in real annular chambers. A modified WKB method is used to solve the wave equation for the acoustic field, and an analytical solution with a wide range of applications is derived. The derivation of the equations requires assumptions such as low Mach number, high frequency and small non-uniformity. Cases with arbitrary distributions of cross-sectional surface area and mean temperature can be solved by the piecewise method as long as the assumptions are satisfied along the entire chamber.
